About 500 hardline vigilantes have taken to the streets of Tehran, demanding authorities crack down on women who wear colourful headscarves and figure-hugging coats which they denounce as "prostitution".
Tehran's hardline authorities have announced a clampdown on women who do not dress suitably modestly but the crowd, mainly composed of long-shirted black-bearded men, called on the police and new conservative parliamentarians to do more.
"The promotion of bad dress codes is the desire of arrogant powers, shame on the government," chanted the crowd on Friday, punching the air with their fists.
"Arrogant powers" is hardline rhetoric usually referring to the United States, Britain and Israel.
"We object to street prostitution and vice," read one placard brandished by protesters.
Dress codes eased a little after the election of reformist President Mohammad Khatami in 1997 but hardliners are trying to claw back these concessions since their conservative allies retook parliament in May.
Many Tehran girls wear heavy make-up, tight jackets, glitzy jewellery and bright headscarves that allow their hair to spill out.
The placards were signed by the conservative Ansar-e Hizbollah group which last year manned checkpoints around parts of Tehran where student demonstrations turned violent.
Witnesses said they saw the group's vigilantes thrashing people with sticks during the student protests.
"A proper dress code is defined by our religion and allows women to expose only their faces and hands," said a middle-aged female protester, one of more than 100 dressed in the all-enveloping black chador.
"We hate these girls who go around all dolled up in the streets."
One member of the Ansar-e Hizbollah, who declined to be named, said this was the first stage of the group's campaign but he did not reveal what the next would be.
Ansar-e Hizbollah members declined to comment on France's ban on Muslim headscarves in state schools.
The crackdown on dress has also targeted shop-window mannequins who must now wear the veil.